Retirement, Other Postretirement Benefits, And Defined Contribution Plans Investments Held For Qualified Pension And Other Postretirement Plans Measured At Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Qualified Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Cash	$ 10,601	$ 123,153
Other pending transactions	(13,813)	11,125
Less: Other postretirement assets included in total investments	(61,285)	(79,360)
Defined Benefit Plan, Plan Assets, Amount	5,242,098	6,993,110
Qualified Pension Plans [Member] | Defined Benefit Plan, Equity Securities, US [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	12,178	16,231
Qualified Pension Plans [Member] | Defined Benefit Plan, Equity Securities, Common Stock [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	807,437	1,001,169
Qualified Pension Plans [Member] | Defined Benefit Plan, Common Collective Trust
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	2,516,688	3,123,111
Qualified Pension Plans [Member] | U.S. Government securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	673,348	627,148
Qualified Pension Plans [Member] | Corporate Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	525,184	966,616
Qualified Pension Plans [Member] | Registered Investment Company
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	750,454	1,129,070
Qualified Pension Plans [Member] | Other Debt Obligations
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	15,395	68,886
Qualified Pension Plans [Member] | Other Contract
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	5,911	5,961
Qualified Pension Plans [Member] | Defined Benefit Plan Total Plan Assets
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	5,306,595	6,938,192
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Other pending transactions	486	(25,897)
Plus: Other postretirement assets included in the investments of the qualified pension trust	61,285	79,360
Defined Benefit Plan, Plan Assets, Amount	623,824	771,319	$ 737,866
Other Postretirement Benefits Plan [Member] | Defined Benefit Plan, Common Collective Trust
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	241,676	312,594
Other Postretirement Benefits Plan [Member] | U.S. Government securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	147,939	152,191
Other Postretirement Benefits Plan [Member] | Corporate Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	113,273	152,562
Other Postretirement Benefits Plan [Member] | Registered Investment Company
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	3,016	28,450
Other Postretirement Benefits Plan [Member] | Other Debt Obligations
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	56,149	72,059
Other Postretirement Benefits Plan [Member] | Defined Benefit Plan Total Plan Assets
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	562,053	717,856
Fair Value Inputs Level 1 [Member] | Qualified Pension Plans [Member] | Defined Benefit Plan, Equity Securities, US [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	12,178	16,231
Fair Value Inputs Level 1 [Member] | Qualified Pension Plans [Member] | Defined Benefit Plan, Equity Securities, Common Stock [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	807,437	1,001,169
Fair Value Inputs Level 1 [Member] | Qualified Pension Plans [Member] | U.S. Government securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0	0
Fair Value Inputs Level 1 [Member] | Qualified Pension Plans [Member] | Corporate Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0	0
Fair Value Inputs Level 1 [Member] | Qualified Pension Plans [Member] | Registered Investment Company
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	221,582	92,347
Fair Value Inputs Level 1 [Member] | Qualified Pension Plans [Member] | Other Debt Obligations
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0	0
Fair Value Inputs Level 1 [Member] | Qualified Pension Plans [Member] | Other Contract
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0	0
Fair Value Inputs Level 1 [Member] | Qualified Pension Plans [Member] | Defined Benefit Plan Total Plan Assets
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	1,041,197	1,109,747
Fair Value Inputs Level 1 [Member] | Other Postretirement Benefits Plan [Member] | U.S. Government securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	69,503	62,240
Fair Value Inputs Level 1 [Member] | Other Postretirement Benefits Plan [Member] | Corporate Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0	0
Fair Value Inputs Level 1 [Member] | Other Postretirement Benefits Plan [Member] | Registered Investment Company
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	3,016	28,450
Fair Value Inputs Level 1 [Member] | Other Postretirement Benefits Plan [Member] | Other Debt Obligations
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0	0
Fair Value Inputs Level 1 [Member] | Other Postretirement Benefits Plan [Member] | Defined Benefit Plan Total Plan Assets
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	72,519	90,690
Fair Value Inputs Level 2 [Member] | Qualified Pension Plans [Member] | Defined Benefit Plan, Equity Securities, US [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0	0
Fair Value Inputs Level 2 [Member] | Qualified Pension Plans [Member] | Defined Benefit Plan, Equity Securities, Common Stock [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0	0
Fair Value Inputs Level 2 [Member] | Qualified Pension Plans [Member] | U.S. Government securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	673,348	627,148
Fair Value Inputs Level 2 [Member] | Qualified Pension Plans [Member] | Corporate Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	525,184	966,616
Fair Value Inputs Level 2 [Member] | Qualified Pension Plans [Member] | Registered Investment Company
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	2,595	3,004
Fair Value Inputs Level 2 [Member] | Qualified Pension Plans [Member] | Other Debt Obligations
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	15,395	68,886
Fair Value Inputs Level 2 [Member] | Qualified Pension Plans [Member] | Other Contract
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	5,911	5,961
Fair Value Inputs Level 2 [Member] | Qualified Pension Plans [Member] | Defined Benefit Plan Total Plan Assets
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	1,222,433	1,671,615
Fair Value Inputs Level 2 [Member] | Other Postretirement Benefits Plan [Member] | U.S. Government securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	78,436	89,951
Fair Value Inputs Level 2 [Member] | Other Postretirement Benefits Plan [Member] | Corporate Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	113,273	152,562
Fair Value Inputs Level 2 [Member] | Other Postretirement Benefits Plan [Member] | Registered Investment Company
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0	0
Fair Value Inputs Level 2 [Member] | Other Postretirement Benefits Plan [Member] | Other Debt Obligations
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	56,149	72,059
Fair Value Inputs Level 2 [Member] | Other Postretirement Benefits Plan [Member] | Defined Benefit Plan Total Plan Assets
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	247,858	314,572
Fair Value Inputs Level 3 [Member] | Qualified Pension Plans [Member] | Defined Benefit Plan, Equity Securities, US [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0	0
Fair Value Inputs Level 3 [Member] | Qualified Pension Plans [Member] | Defined Benefit Plan, Equity Securities, Common Stock [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0	0
Fair Value Inputs Level 3 [Member] | Qualified Pension Plans [Member] | U.S. Government securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0	0
Fair Value Inputs Level 3 [Member] | Qualified Pension Plans [Member] | Corporate Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0	0
Fair Value Inputs Level 3 [Member] | Qualified Pension Plans [Member] | Registered Investment Company
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0	0
Fair Value Inputs Level 3 [Member] | Qualified Pension Plans [Member] | Other Debt Obligations
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0	0
Fair Value Inputs Level 3 [Member] | Qualified Pension Plans [Member] | Other Contract
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0	0
Fair Value Inputs Level 3 [Member] | Qualified Pension Plans [Member] | Defined Benefit Plan Total Plan Assets
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0	0
Fair Value Inputs Level 3 [Member] | Other Postretirement Benefits Plan [Member] | U.S. Government securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0	0
Fair Value Inputs Level 3 [Member] | Other Postretirement Benefits Plan [Member] | Corporate Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0	0
Fair Value Inputs Level 3 [Member] | Other Postretirement Benefits Plan [Member] | Registered Investment Company
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0	0
Fair Value Inputs Level 3 [Member] | Other Postretirement Benefits Plan [Member] | Other Debt Obligations
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0	0
Fair Value Inputs Level 3 [Member] | Other Postretirement Benefits Plan [Member] | Defined Benefit Plan Total Plan Assets
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	$ 0	$ 0